Porous Nanomaterials

Porous Nanomaterials List

Porous nanomaterials are one of the first known nanomaterials, and natural molecular sieves began to be used about 250 years ago. Because the size scale of porous nanomaterials is located in the intersection region of atomic cluster and macroscopic object, they have surface effect, small size effect, quantum size effect and macro quantum effect, and many unique mechanical, electrical, magnetic, optical, thermal and chemical properties can be obtained. Compared with bulk materials and general nanomaterials, porous nanomaterials have many properties such as large specific surface area, high porosity, low density, high transmissibility, assemblability and high absorbability, which has a broad application prospect.

Applications:

Based on the unique properties, porous nanomaterials have been widely used in many industries.

• Gas storage field: Taking the advantages of large specific surface area and high porosity, porous nanomaterials can be used in the gas storage field, which is helpful for new energy developing.

Figure 1. An example of porous nanomaterials applied in gas storage field.

• Adsorption separation field: With the rapid development of industry, the emission of H₂S, SO₂, NOx and formaldehyde is increasing day by day, which brings serious harm to people's life and environment. Adsorption separation is an efficient way to separate harmful gases, which is very effective for air purification. The adsorbent is the key in this method. Porous nanomaterials are ideal choices due to their large specific surface area, high porosity and high absorbability, and have a broad application prospect.

Figure 2. An example of porous nanomaterials applied in adsorption separation.

• Catalyst field: Porous nanomaterials with complex and variable structures which is a kind of catalysts with excellent performance. As catalysts, porous nanomaterials have been widely used in oxidation reaction, acid catalysis reaction and hydroxylation reaction, which can reduce the requirement of reaction conditions and increase the reaction rate. For example, mesoporous ZrO₂ is widely used as catalytic carrier material in automobile exhaust treatment.

Figure 3. Porous nanomaterial applied in catalyst field.

• The others: In addition to the above mentioned, porous nanomaterials also are widely used in the fields of chromatographic separation, electromagnetism, drying field, protein delivery and the others.

Classification:

According to the pore size, porous nanomaterials can be divided into the following categories:

• Microporous materials: Microporous materials with a pore diameter of less than 2 nm mainly include zeolites, molecular sieves, activated carbon and the others.
• Mesoporous materials: The pore size of mesoporous materials ranges from 2 nm to 50 nm, including aerosols layered clays, M41S series, SBA series, MSU series and the others.
• Macroporous materials: The pore diameter of macroporous materials is greater than 50 nm, mainly including porous glass, 3DOM and the others.

References

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2. Ma Y, Wang Z, Xu X, et al. Review on porous nanomaterials for adsorption and photocatalytic conversion of CO₂[J]. Chinese Journal of Catalysis, 2017, 38(12):1956-1969.
3. Ben T, Pei C, Zhang D, et al. Gas storage in porous aromatic frameworks (PAFs)[J]. Energy & Environmental ence, 2011, 4(10):3991-3999.